The Ancient Volcanoes of Great Britain, Volume 1 (of 2)Note 176 — Chapter XII · CHARACTERS OF THE SILURIAN SYSTEM IN BRITAIN. THE ARENIG VOLCANOESReading editionAnnual Report of the Geol. Surv. for 1895, p. 27 of reprint.◇Copy noteReturn to CHAPTER XII CHARACTERS OF THE SILURIAN SYSTEM IN BRITAIN. THE ARENIG VOLCANOES